Automated medical analyzers perform medical tests on a sample, such as biological liquids, e.g., whole blood, blood plasma, blood serums, urine, etc. These tests may require mixing of the sample with a liquid, such as a reagent. Once the sample is mixed with the liquid, a chemical reaction may take place. The chemical reaction can be used to provide a medical professional with medical information about the sample and thus a medical condition of a patient.
Liquids, such as samples and reagents, are often moved from one location within the analyzer, such as sample or reagent vials moved on carousels, to another location within the analyzer, such as test region, e.g., having test tubes or the like. Many analyzers use a hollow probe carried by a robot arm to accomplish this. Specifically, the probe is inserted into the liquid, and some of the liquid is drawn into the probe. The liquid is subsequently expelled from the probe into the test tube for testing.
One problem is that the probe becomes contaminated on its interior and exterior with the liquid and cannot be used for another liquid while contaminated. One method for dealing with contamination is to connect a disposable probe tip to the probe. In operation, the tip is inserted into the liquid, and the liquid is drawn into the tip. The liquid is then expelled, and the tip is replaced with a new tip for the next liquid. However, this becomes impractical and expensive for many analyzers.
Some analyzers reuse the same probe for successive tests and clean the probe between each test. One method for cleaning the probe involves pumping a cleaning liquid, such as a buffer, through the probe while the probe tip is inserted into a shallow cup. The cleaning liquid exits the probe tip and fills the cup to immerse the tip in the cleaning liquid. Then, the cleaning liquid is pumped onto the exterior of the probe. One problem with this is that separate pumps are usually used to pump the cleaning liquid through the probe and onto the probe exterior. Another problem is that the cleaning liquid is directed at a single location on the probe exterior, making it difficult to clean the entire probe exterior. Other problems include increased wash times, an increased volume of cleaning liquid, and/or increased operating pressures.
For the reasons stated above, and for other reasons stated below which will become apparent to those skilled in the art upon reading and understanding the present specification, there is a need in the art for alternative probe cleaning apparatus and methods.